When the Chargers overhauled their coaching staff in recent weeks, John Pagano was the top-ranking survivor.

Pagano, 45, will enter his second season in charge of the defense. In that regard, the Chargers want him to fare more like Ron Rivera and Wade Phillips than like Ted Cottrell and Dale Lindsey.

Rivera’s second full season, in 2010, with Pagano as his linebackers coach, saw the Chargers lead the NFL in total defense and improve one spot in points allowed, to 10th.

Phillips ran the defense from 2004 to 2006. Each year, the yardage-allowed ranking improved, while the defense went from 11th to 13th to seventh in points given up.

Both Rivera and Phillips went directly from the Chargers to head-coaching jobs in the NFL.

The Chargers hired Cotrell when they were in a bind after Marty Schottenheimer’s surprising dismissal, which came four weeks after the team’s loss in the 2006 playoffs.

Cottrell’s first Chargers defense, which got 10 interceptions from Antonio Cromartie, led the NFL in takeaways and was fifth in points allowed. But midway through the next season, the Chargers fired Cottrell and replaced him with Rivera, the linebackers coach.

Lindsey, hired by Schottenheimer, didn’t return for a third season after his defense in 2003 finished 31st in points allowed, 28th in takeaways and 21st in yards.

Pagano's time spent as an assistant to Rivera is a positive. Another mentor to Pagano is his brother, Chuck, the Colts' head coach and a former Ravens defensive coordinator. Pagano appears to be on a good career path, but his defense will need to be more consistent in 2013.